Improvement in processes of refining and whitening the products from sulphurets of



UNITED STATES PATENT OFFICE,

GEORGE 'r. LEWIS, on PHlLADELPHIA, PENNSYLVANIA.

I MPROVEMENT IN,PROCESSES 0F REFINING AND WHITENING THE PRODUCTS FROM SULPHURETS 0F -LEAD AND ZINC.

Specification forming part of Letters Patent N0. 112,606, a ed March 14, 1 71 To all whom it may concern Be it known that .I, GEORGE T. LEWIS, of

the city and countyofPhiladelphia, in the State of Pennsylvania, have invented a new and useful Process of Refining and Whitening the Products of the Sulphurets of Lead and Sulphurets of Zinc,which invention is supplementary to the treatment of sulphurets of zinc and lead (either as single sulphurets or as mixed sulphurets)with fuel and a dust-blast,for the purpose of vobtaining 1 lead white, zinc white, or lead and zinc white, byeollectin g the products in abag room, orotherwise; and I do hereby declare thefollowing to be a full, clear, and

exact description of my said invention, which will enable others skilled in the art to which it appertainsto practice the same."

The nature of my said invention eonsists'in passing the product which is obtained'by burning a mixed charge of fuel and the sulphuret ores of zinc and lead, as above, through a metallic or other infusibletube heated toredness.

I take a tube about twelve inches in diameter andabout six feet long and mounted on an axle in an inclined direction, so that it can be constantly revolved. The product of the G011]- bustion of the ores of zinc and lead above mentioned, after being caught in the bag room or other collecting-chamber, as is usually done, is conveyed to the upper end of the inclined revolving cylinder or tube and caused to slide through with such velocity as shall insure athorough treatment by the heat and air in its passage. The revolving cylinderis kept heated to a low red heat bya furnace underneath.

Having thus described my invention, what I claim is i The process of refining and whitening of the products obtained by reducing the sulphurets of lead and zinc with fuel by passing these products through a heated tube, substantially as described.

, GEORGE T. LEWlS. Witnesses:

WM. R. WRIGHT, CHAS. M. GREEK. 

